Many types of communications can be performed over data networks (wireless and/or wireline networks), including electronic mail, web browsing, file downloads, electronic commerce transactions, voice or other forms of real-time, interactive communications, and others. To enable the establishment of communications sessions in a network, various control functions are deployed in the network. Some standards bodies have defined subsystems within communications networks that include such control functions. One such standards body is the Third Generation Partnership Project (3GPP), which has defined an Internet Protocol (IP) multimedia subsystem (IMS) that includes various control functions for provision of IP packet-switched multimedia services, including audio, video, text, chat, or any combination of the foregoing.
Another standards body is the Third Generation Partnership Project 2 (3GPP2), which as defined a multimedia domain (MMD) network to provide packet-switched multimedia services. In the wireline context, the equivalent of an IP multimedia subsystem is sometimes referred to as a Next Generation Networks (NGN).
Services of a packet-switched services network (e.g., IMS network, MMD network, or NGN network) may be accessed by users within an enterprise network. An “enterprise network” refers to a network associated with an enterprise, such as a company, educational organization, or government agency. An “enterprise network” can also refer to a customer network such as a home network or small office network. In one scenario, the packet-switched services network can be considered to be a services “overlay” network that provides services accessible by users of an enterprise network. Typically, the enterprise network has an aggregation device (such as a femtocell base station, a set-top box proxy server that serves multiple set-top boxes, etc.) through which enterprise network users can access the external packet-switched services network. However, an enterprise network user may not have an explicit identity provisioned in the packet-switched services network. Although the aggregation device has an identity provisioned in the packet-switched services network, using the identity of the aggregation device alone does not provide the packet-switched services network enough context to perform communications, such as to route a terminating call request to a specific subscriber device.